Five multi-metal bactericides containing Cu as minor component, Cu-Mg (MM25C75M), Cu-Zn (MM25C75Z), Cu-ZnO (MM20C80Z), Cu-ZnS (MM17C83Z), Cu-Mg-Zn (MM17C17Mg66Zn) and four respective controls without Cu (i.e. coated Mg, Zn, ZnO, ZnS) were synthesized and delivered to UF collaborator Dr. Johnson to support 2020 field trial. A relatively new Ray Ruby’ grapefruit block with windbreaks was selected in Vero Beach area. In vitro antimicrobial studies were performed using Xanthomonas alfafae as citrus canker surrogate as part of QC protocol. The minimal inhibitory concentration (MIC) was in the range of 128ppm Mg / 32ppm Cu for MM25C75M C, 32ppm Zn / 8ppm Cu for MM25C75Z, 32ppm Zn / 16ppm Cu / 16ppm Mg for MM17C17M66Z, 16ppm Zn / 4ppm Cu for MM20C80Z, and 512ppm Zn / 103ppm Cu for MM17C83Z. Additional studies on Minimal Bactericidal Concentration (MBC) and Colony Forming Units (CFU) were also performed. MM20C80Z and MM25C75Z demonstrated bactericidal activity at 32ppm Zn / 8ppm Cu, while MM25C75M and MM17C1766Z showed MBC at 512ppm Mg / 128ppm Cu and 64ppm Zn / 16ppm Cu / 16ppm Mg, respectively. MM17C83Z did not present bactericidal activity. Quality of all the treatments remain the same as the last year. All treatments are being evaluated this season (metallic Cu at 0.5 lb/acre) for yield, fruit size and disease incidence. Trial results will be reported by the end of the trial season. Additional material characterization results on systemic activity will be reported in coming months.